I have a 91 ford ranger 3.0 fuel injected standard. I have problems with my car starting it wont idle when its cold. If i let it warm up for about three minutes it is fine but when its cold it surges. Whats wrong with it?

The possibility of being a weak fuel pump. Of coarse there are many sensors on your car. One of thoes could be bad too. Maybe check the one on you exhaust system. It should be between the muffler, and the engine. It should be a plug with probably 2 wires on it. Sometimes it goes bad and confuses you main engine brain box. This may be the cheapest one to replace also. You can also unplug it. This may or may not change anything. It wont hurt to run without it being hooked up either. At least on the 5.0's.

it is not working very well

call car talk on saturday from 10-11 am

I'd start with a basic tuneup. You did not mention if or when you had changed the plugs, wires, ETC. also if you have acces.. have a scan tool hooked up while engine is cold, look at the data and see what the engine coolant sensor is reading.... it may be out of range and need replaced... reading too cold a temp... thus a too rich setting at first

I had the same problem with my 1991 ranger 3.0 back in 1992, it acted like a carbureted engine with a bad automatic choke, even though it's actually fuel injected. Once mine warmed up, it too ran just fine. My code scanner said the TPS (Throttle Position Sensor Voltage was low). I replaced it (on left side of throttle intake) & that fixed it.
Screamer141

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1991 Ranger XLT 3.0 V-6, 5 speed Mazda R1, Long Bed
244,000 + miles